Air Filters come in a variety of shapes and sizes and deciding which one is best for you can be a difficult decision. In order to make choosing easier, the heating and air industry developed the MERV rating system to inform you about the effectiveness of different filters. So what is a MERV rating and how can it help you choose a filter for your HVAC system?MERV RATING
MERV stands for minimum efficiency reporting value. This is a number assigned to an air filter that describes how effective it is at removing particles from the air inside your home.
Air filters are assigned a MERV rating between 1 and 16, depending on their effectiveness. The higher the MERV rating of an air filter, the better the filter is at removing particles. MERV ratings are often grouped into categories that describe the minimum particle size that they are able to filter out. The categories are listed below.
* MERV 1-4 Effective at removing particles greater than 10 microns in size, such as pollen and dust mites.
* MERV 5-8 Effective at removing particles greater than 3 microns in size, such as mold and pet dander.
* MERV 9-12 Effective at removing particles greater than 1 micron in size, such as legionella and lead dust.
* MERV 13-16 Effective at removing particles greater than 0.3 microns in size, such as bacteria and insecticide dust.
CAUTION ABOUT AIR FLOW
Although higher MERV ratings are better at removing small particles from the air, they also restrict air flow to your air conditioner. That’s because the material on filters with high MERV ratings is denser, which makes it harder for air to pass through them. To figure out what filter best matches your air quality needs and cooling specifications, it’s best to consult a certified HVAC contractor like MTB Heating and Air.